Answer:
The minimum resistance is 25 ohms.
Explanation:
Resistance of each resistor is 100 ohms. When resistors are connected in parallel, the equivalent resistance is lowest. For parallel combination, the equivalent resistance is given by :
Here, all resistors are 100 ohms. So,
So, the minimum resistance is 25 ohms.
Answer:
0.1 M
Explanation:
Molarity = number of moles / litres of solution.
4 g of calcium bromide = 0.02 mol
(found by dividing 4 g by the atomic mass of CaBr2, which is 199.886)
200 mL of solution = 0.2 litres
Molarity = 0.02 mol / 0.2 L = 0.1 M
56km/s is 201600m/hr to its equivalent.
Answer: The coefficient in front of nitric acid is 2
Explanation:
According to the law of conservation of mass, mass can neither be created nor be destroyed. Thus the mass of products has to be equal to the mass of reactants. The number of atoms of each element has to be same on reactant and product side. Thus chemical equations are balanced.
The salts which are soluble in water are designated by symbol (aq) and those which are insoluble in water and remain in solid form are represented by (s) after their chemical formulas. Liquids are represented by (l) and gases are represented by (g).
The balanced chemical reaction is :
Based on the balanced chemical reaction presented above, every mole of magnesium (Mg) yields one mole of diatomic hydrogen (H2). When converted to masses, every 24.3 grams of magnesium yields 2 grams of hydrogen.
From the given, there are 20 grams of magnesium available for the reaction. With this amount, the expected yield of hydrogen is 1.646 grams. To calculate the percent yield, divide the actual yield to the hypothetical yield.
*The case is impossible because the actual yield is greater than the theoretical yield.
If we assume that there had been a typographical error and that the actual yield is 0.7 grams instead of 1.7 grams, the percent yield becomes 42.5%. Thus, the answer is letter E.
